This invention relates to an X-ray apparatus for diagnosis and in particular an X-ray apparatus for effecting an automatic X-ray photographing using an X-ray television device.
X-ray apparatus is known for use in the medical field for diagnostics is adapted to expose a patient to X-rays and send the X-rays which penetrate through the patient to an X-ray film to obtain an X-ray image. X-ray apparatus is also well known which can obtain a dynamic X-ray image using a so-called X-ray television device adapted to convert an X-ray image from a patient to an optical image for display on a television monitor. Such an X-ray apparatus is disclosed in U.S. Pat. No. 3,622,786.
A known method is often used by which an X-ray photograph is taken at a proper X-ray exposure timing while observing an X-ray image through a fluoroscope. According to this method an X-ray image corresponding to a region of interest (hereinafter called ROI) in a patient can be obtained by alternately manually effecting a fluoroscopic examination of an X-ray image and an X-ray exposure for photographing. It is, however, difficult to X-ray photograph RCI of a patient, such as a esophagus, through which a contrast medium (for example, barium) is passed at high speed. The reason is that because an X-ray exposure command for photographing such ROI of the patient is given by a manual operation of an operator it is difficult to obtain the timing at which such a command must be imparted. In consequence, the quality of the photograhy is greatly dependent upon the skill of the operator. since the timing at which an excellent X-ray photograph is obtained is momentary in nature, the operator must constantly observe an X-ray image on the TV monitor, while in a state of high tension, thus imparting agreat burden to the operator. Furthermore, it is difficult to judge the timing at which an excellent X-ray photograph is gained. If such a timing is improper, a photographing operation must be repeated again and again. As a result, the patient is exposed to an excessive dosage of X-ray, thus involving a eventual safety problem.